Surgical pump



June 2o, 1944. J; c. MARSH 2,351,828

SURGICAL PUMP Filed Jan. 8, 1942 P121. q V7.5

SM- @7m Patented June 20, 1944 f SURGICAL PUMP Jack C. Marsh,Pittsburgh, Pa., assignor to G. L. Meyers and G. H. Drumheller, Jr.,both of Aspinwall, Pa.

Application January 8, 1942, Serial No. 425,999

' Claims. y (Cl. 103-148) This invention relates to continuous dripapparatus and it has particular relation to a surgical pump suitable forthe gradual administration of liquid compositions in the treatment ofailments, such as peptic ulcer, or the removal of fluid from the tubularorgans.

One of the objects of the invention isto provide a surgical pump inwhich the delivery rate of the liquid is positive and the rateaccurately maintained.

Another object of the invention is to provide a surgical pump in whichan automatically controlled unit regulates the ow of liquid to thepatient. Other objects may be inferred from the nature of the invention.

I Heretofore the apparatus employed has depended on suction obtained byallowing water to flow from a bottle suspended above the patient througha tube to a bottle placed below the patient. When the rate of ow ofwater is 'changed the air pressure in the chamber also changes. As theair regulates the flow of liquid to the patient the rate of flow wouldnecessarily fluctuate and which in an apparatus of this type cannot beadjusted accurately. Pumping apparatus have heretofore been employed toovercome the above objections but they have been unsatisfactory dueeither to lack of control of the suction formed in the operation of theapparatus or failure of accurately controlling the delivery rate of thepump, particularly in the smaller quantities, i. e. amounts of from veto fteen drops a minute.

Inuthe use of a surgical pump constructed in accordance with myinvention, the pump is positioned beside the patient. The pump is formedwith a constant speed motor provided to drive a plurality of camelements, which engage ngers adapted to contact a tube, the tubeextending from a source of supply to a patient. A time control deviceconnected to the motor through a microswitch is provided to regulate theaction of the pump. The time control permits the pump to 'deliver asingle stroke of the pump, five drops of fluid, after which the pumpstops for a time. This stop or wait may be adjusted from less than asecond to more than sixty seconds by means of a control knob operativelyconnected to the timer control. As soon as the pump has created asuction more than equal to a column of Water two feet six inches high, avacuum control operatively connected to the tube shuts ofi the pump,while maintaining the vacuum. As soon as the vacuum is broken the pumpis automatically turned on again and operates until such time as morethan the designated acquired.

For a better understanding of the invention, referencemay now be had tothe accompanying drawing forming a part of the specification in which:

Fig. l is a plan View of thel invention, with certain portions insection for the sake of clearness.

Fig. 2 is a diagrammatic view of an electrical circuit employed in theinvention.

In practicing my invention, the fluid is placed in a container IIJ, atsubstantially the same level as the patient, with the tube I2, formed ofrubber or other elastic material, extending from the container to thepatient. A pumping apparatus I3, contained in a casing I4, having abracket I5, formed with a member Il adapted to engage the tube I2, asindicated at I8, is provided to feed fluid to or from the patient asdes-ired.

The pumping apparatus is provided with a plurality of cams 20, 2l, and22 adapted to engage suction is lingers 23, 24, and respectively. Eachof the fingers, formed with end members 2'I adapted to compress the tubeI2, is provided with springs 28 positioned in openings 29 of a block 30.The

member 21 of the fingers 23 and 25 have edge portions which engage thetube I2. These fingers are provided to entrap thelud in the tube betweenthe two points of engagement. The iinger 24 is provided to act as apiston, for forcing the liquid to the patient and is formed with theedge portion of the member 21 extending longitudinally of the tube I2.The springs maintain the fingers in contact with the cams. The cams aremounted on a shaft 32 supported in a housing 33, with the shaft beingdriven by a motor 34 through reduction gearing 35 integral with themotor.

A microswitch element 31 mounted on the housing 33 and actuated by thecam 2| is provided with a lead 39-connected to the motor 34 togetherwith a lead 40 connected to a condenser 4I of a time control device 42.The time control 42 is also provided with a relay 43, having connectedthereto a lead 44 extending to the motor and a vacuum or rectifier tube43, having a lead 41 connected to one'side of the condenser 4I.Extending from the condenser to a time control dial 49 mounted on thecasing I4 is a lead 59, operately connected to the condenser. Leads 5Iand 52 extending from the control dial are connected to the relay 43 andto the vacuum tube'46 respectively. A toggle switch 54 mounted on the`casing I4 is provided with a lead 55, connected to connected to thevacuum or rectifier tube 46. A

resistance cord 59 is connected at one end to the lead 51 and at theother end to the relay 43. A switch B5, of a control device 56 isprovided with a lead 61 connected to a vacuum or rectiiier tube 46, andalead 68 coimected to the relay 43. The switch 65 is provided with acontact element 15 normally held in engagement with bellows 1l, formedof rubber or other elastic material. Connected to the bellows on theside opposite the switch is a tube 13 connecting to the bellows and thetube l2, intermediate the lingers and the patient.

In operation, the cams 2U, 2l and 22 are driven by the motor 34, so thatat least one finger is always compressing the tube l2; -for example, asshown in Fig. 1, with the finger closed against the tube. In startingthe pump a suction is created by compressing and expanding the tube l2,for example when linger 214 compresses the tube. As the cams rotate, thefinger V'24 moves back and finger 25 closes. When iinger 24 moves back,it releases the tube l2, which expands and fills from the supplycontainer le. With finger 24 back and the outlet end closed by finger25, the finger 23 moves forward closing the inlet end of the tube andremains in such position until linger 25 moves back from the tube, withfinger 24 moving forward driving over the required amount of fluid. Asone iinger is always closed, there is a closed system maintained at-alltimes. At the end of each stroke of the pump, the cam 2i actuates theswitch 31 which stops the pump fer a time. This stop or wait can beadjusted from less than a second to'more than sixty seconds, dependingon the dial setting 49, before making another stroke. The operation ofthe time control depends upon the principle that the time required todischarge an electrical condenser through a resistance depends upon thecharging potential applied to the condenser. s

As soon as the pump has-created a suction more than equal to a column ofwater two feet six inches high, the vacuum control shuts ofi the motor.As shown in Fig. l, the Contact -element 13, of the switch 65, engages aside of the bellows 1l which normally maintain the switch in closedposition. When more than the ldesired suction is exerted, the bellowscontract, thus opening the switch and stopping motor, `while maintaininga vacuum. This is particularly important in the removal of fluidand gasYfrom the duodenum. As soon as the vacuum is broken by the removal ofthe fluid and gas from the duodenum, the purnp is automatically startedand operates until two feet six inches of negative pressure is againobtained.

From the foregoing description it is apparent that I have provided vasurgical pump having electrically controlled means which .providesintermittent operation of the pump, together with a structure whichpermits wide variation .of the quantities of fluid delivered to or.removed from the patient. Moreover itis apparent thathave provided astructure that is simple in operation,

accurate in the function thereof and which, when once set, may beoperated by a novice of the medical profession.

It is to be understood that the form of the invention herewith shown anddescribed is merely illustrative of a preferred embodiment and that suchchanges as fall within the purview of one skilled in the art may be madewithout departing from the spirit of the invention and the scope of theappended claims.

I claim:

l. A pumping apparatus for medical treatments lcomprising a constantspeed motor, a plurality of cam elements operated by the motor, aplurality of nii-gers actuated by the cams, in a predetermined.sequence, an elastic tube adapted to be compressed by the fingers, anelectrical time control for cont-rolling the action of the pump andmeans connected with the time control for regulating the delivery rateof the pump.

2. A pumping apparatus for medical treatments comprising a constantspeed motor, a plurality of cam elements operated by the motor, aplurality of fingers actuated by the cams, in a predetermined sequence,an elastic tube adapted to be compressed by the ngers, anelectricalvtime control for controlling the action of the pump, a switchelement operatively connected with one of the cams, for actuating thetime control and means connected to the time control for regulating saidtime'control.

3. A pumping apparatus for medical treatments comprising a constantspeed motor, a plurality of cams operated by the motor, a plurality .offingers actuated by the cams, in a predetermined sequence, an elastictube adapted to be .compressed by the fingers, an electrical timecontrol including a condenser for controlling the action of the pump, aswitch element operatively `connected with one of the cams for actuatingthe time control and means connected with the .conf denser forregulating the time control.

4. A pumping apparatus for medical treatments comprising a constantspeed motor, a plurality of cam elements operated by the motor, aplurality of lingers actuated by the cams, in apredetermined sequence,an elastic .tube .adapted ,to be compressed by the fingers, for creating,a suction, means secured to the tube Yfor-stopping the pump uponcreation -of a suction above a predetermined point, an electrical timecontrol for controlling the intermittent operation of .the pump andmeans operatively connected `to the time control for regulating saidtime control.

5. A pumping apparatus 'for medical ,treatments comprising a constant.speed motor, a plurality of cam elements operated Vby the motor, a,plurality of nngers actuated by the cams, in =a predetermined sequence,an elastic tube 4adapted to be compressed by the Vfingersfor creating ,asuction, a vacuum control element secured `to .the tube for stopping thepump .upon creation of .a suction above a predetermined point andv`electrical means for intermittently .operating `.the pump. f V

JACKC.

